I don't blame anyone who thinks I have aquarium ADD this month. I have come up with some new plan every week!

My plans have taken a major change though. Just when I thought my mean ol hubby would never come around on the idea of me getting a big tank, he did. For valentines day he surprised me by telling me he wanted to use our tax return to get me my big community tank that I've been wanting. I just need advice about a used setup that I am thinking of buying.
It's a tank that is 48" x 24" x 18" inches. So aqadvisor says 90 gallons?
It comes with 2 Fluval 405 filters and a magnum 350 canister filter, also a coralife light fixture, heaters, stand, full hood, two power heads and a cleaning kit.
It has been used for a saltwater tank for the last year. He is asking $350. I have watched the classifieds very closely for the last several months and 55 gallon tanks with hob filters and no hoods regularly go for about $200 in my area. Do you guys think this is a good deal? Am I likely to have any problems using equipment that was previously used for saltwater on a freshwater tank?
Thanks guys!